The invention relates to the field of optical communications, and in particular to chromatic dispersion using optical resonators.
A number of devices have been used for dispersion in communication systems, such as tunable fiber gratings, optical all-pass filters using a ring resonator and virtually imaged phased array devices Tunable fibers can provide high dispersion over large bandwidths, and significant tunability. However, these devices operate in reflection mode that requires an optical circulator to retrieve the reflected signal, which increases the complexity of the device. The optical all-pass filters and the virtually imaged phased array devices exhibit periodic responses, which may not suitable for high bit-rate applications. Also, the all-pass filter designs are based upon a waveguide geometry that tends to exhibit significant polarization mode dispersion, an undesirable characteristics for chromatic dispersion compensation.